Method for the cleaning of delicate surfaces

ABSTRACT

Compositions are disclosed which are suitable for the safe cleaning of delicate surfaces, i.e. marble and lacquered surfaces, e.g. lacquered wooden floors. The compositions disclosed herein comprise at least one anionic surfactant, they are free of strong builders, they are formulated in the mildly acidic to mildly alkaline pH range, and they comprise positive divalent ions in amounts so as to saturate the anionic surfactant in the composition.

TECHNICAL FIELD

The present invention relates to hard surface cleaning compositions. Thecompositions herein are specifically designed for the safe cleaning ofmarble, painted and lacquered surfaces, especially lacquered and paintedwood.

BACKGROUND

A wide variety of cleaning compositions for hard surfaces have beendisclosed in the prior art. Most of these compositions are concernedonly with performance, on a wide variety of stains and in a wide varietyof conditions. And most hard surfaces are rather resistant to the pointthat it is generally not a concern that these surfaces may bepermanently damaged by the cleaning composition.

However marble and lacquered surfaces are two types of surfaces which dorequire particular attention, when formulating cleaning compositions fortheir cleaning. Indeed, marble is mainly composed of calcium carbonate,and is therefore incompatible with cleaning compositions which would beacidic, and/or which would comprise a builder. Indeed, acidity would"dissolve" marble, while the builder, whose function is specifically tobind ions which are present in water and dirt particles, would also bindthe calcium in the marble, thereby turning the surface from very shinyto dull, as the introduced surface irregularities lower the reflectanceof the surface. We have also found that cleaning products formulated atneutral pH and which contain anionics surfactants also damage marble,probably because the anionic surfactants would also bind the calcium inthe marble as described hereinabove. Thus the formulation of an alkalinecomposition free of anionic surfactants would seem indicated in thepresent circumstances.

However, the formulation of an alkaline composition does not accommodatethe cleaning of lacquered and painted surfaces, such as painted metalsurfaces, or lacquered and painted wooden surfaces e.g. lacquered woodenfloors. As used herein, lacquers are typically made out of polyurethanesor polyacrylates or mixtures of both, and paint is mainly pigmentedpolyacrylates, polyvinylacetates or alkydresins. Indeed such surfacesare permanently damaged by alkalinity. Specifically, alkalinity woulddestroy the lacquer and therefore give the lacquered surface theappearance of dullness or a colour change. Thus it would appear thatformulating a cleaning composition which is suitable for cleaning bothmarble and lacquered surfaces is hindered by incompatible pHrequirements.

Also, the absence of an anionic surfactant, which is desirable forpreserving the marble, is somewhat incompatible with a good overallcleaning performance, specifically soil solubilization/greaseemulsification.

Thus it is an object of the present invention to formulate a liquidcomposition which is suitable, i.e. safe, for the cleaning of bothmarble and lacquered surfaces, and which comprises an anionic surfactantso as to provide good cleaning performance, in particular which performswell on grease removal.

In response to this object, we have formulated a liquid compositionwhich comprises at least one anionic surfactant, which is free of strongbuilders, which is formulated at a mildly acidic to mildly alkaline pH,and which comprises positive divalent ions in amounts so as to saturatethe anionic surfactant in the composition.

Indeed, we have found that in the present compositions, the mildlyacidic to mildly alkaline pH damages neither marble nor lacquers. Also,the positive divalent ions in a saturating amount for the anionicsurfactant prevents the damage on marble, while still allowing theanionic surfactant to perform its cleaning action.

Cleaning composition which are said to be for delicate surfaces aredescribed in EP 511 091, CN 1055198 (title) and CN 10 32 360 (title).

SUMMARY OF THE INVENTION

The present invention encompasses a liquid cleaning composition whichcomprises at least one anionic surfactant, which is free of strongbuilders, which is formulated at a mildly acidic to mildly alkaline pH,and which comprises positive divalent ions in an amount so as tosaturate the anionic surfactant in the composition.

The present invention further encompasses a method of cleaning marble orlacquered surfaces, where an effective amount of said composition isapplied to clean said marble or lacquered surfaces, and said compositionis removed.

DETAILED DESCRIPTION OF THE INVENTION

The compositions herein are liquid compositions. They are typicallyaqueous and typically comprise from 10% to 99% by weight of the totalcomposition, preferably from 15% to 95%, most preferably from 30% to 92%of water.

The anionic surfactant

As a first essential characteristic, the compositions herein comprise atleast one anionic surfactant, required for cleaning. Suitable anionicsurfactants for use herein include salts (including, for example,sodium, potassium, ammonium, and substituted ammonium salts such asmono-, di- and triethanolamine salts) of soap, C₉ -C₂₀ linearalkylbenzenesulfonates, C₈ -C₂₂ primary or secondary alkanesulfonates,C₈ -C₂₄ olefinsulfonates, sulfonated polycarboxylic acids prepared bysulfonation of the pyrolyzed product of alkaline earth metal citrates,e.g., as described in British patent specification No. 1,082,179, C₈-C₂₄ alkylpolyglycolethersulfates (containing up to 10 moles of ethyleneoxide); alkyl glycerol sulfonates, fatty acyl glycerol sulfonates, fattyoleyl glycerol sulfates, alkyl phenol ethylene oxide ether sulfates,paraffin sulfonates, alkyl phosphates, isethionates such as the acylisethionates, N-acyl taurates, alkyl succinamates and sulfosuccinates,monoesters of sulfosuccinates (especially saturated and unsaturated C₁₂-C₁₈ monoesters) and diesters of sulfosuccinates (especially saturatedand unsaturated C₆ -C₁₂ diesters), acyl sarcosinates, sulfates ofalkylpolysaccharides such as the sulfates of alkylpolyglucoside (thenonionic nonsulfated compounds being described hereinbelow), and alkylpolyethoxy carboxylates such as those of the formula RO(CH₂ CH₂ O)_(k)--CH₂ COO³¹ M⁺ wherein R is a C₈ -C₂₂ alkyl, k is an integer from 0 to10, and M is a soluble salt-forming cation. Resin acids and hydrogenatedresin acids are also suitable, such as rosin, hydrogenated rosin, andresin acids and hydrogenated resin acids present in or derived from talloil. Further examples are described in "Surface Active Agents andDetergents" (Vol. I and II by Schwart, Perry and Berch). Also suitableanionic surfactants for use herein include alkyl ester sulfonatesurfactants, i.e. linear esters of C₈ -C₂₀ carboxylic acids (i.e., fattyacids) which are sulfonated with gaseous SO₃ according to "The Journalof the American Oil Chemists Society", 52 (1975), pp. 323-329. Suitablestarting materials would include natural fatty acid substances asderived from tallow, palm oil, etc.

Also suitable as anionic surfactants for use herein are alkyl sulfatesurfactants hereof, which are water soluble salts or acids of theformula ROSO₃ M wherein R preferably is a C₁₀ -C₂₄ linear or branchedhydrocarbyl, preferably an alkyl or hydroxyalkyl having a C₁₀ -C₂₀ alkylcomponent, more preferably a C₁₂ -C₁₈ alkyl or hydroxyalkyl, and M is Hor a cation, e.g., an alkali metal cation (e.g., sodium, potassium,lithium), or ammonium or substituted ammonium (e.g., methyl-, dimethyl-,and trimethyl ammonium cations and quaternary ammonium cations such astetramethyl-ammonium and dimethyl piperdinium cations and quaternaryammonium cations derived from alkylamines such as ethylamine,diethylamine, triethylamine, and mixtures thereof, and the like).

Still further suitable anionic surfactants for use herein are alkylalkoxylated sulfate surfactants herein, which are water soluble salts oracids of the formula RO(A)_(m) SO₃ M wherein R is an unsubstituted C₁₀-C₂₄ alkyl or hydroxyalkyl group having a C₁₀ -C₂₄ alkyl component,preferably a C₁₂ -C₂₀ alkyl or hydroxyalkyl, more preferably C₁₂ -C₁₈alkyl or hydroxyalkyl, A is an ethoxy or propoxy unit, m is greater thanzero, typically between about 0.5 and about 6, more preferably betweenabout 0.5 and about 3, and M is H or a cation which can be, for example,a metal cation (e.g., sodium, potassium, lithium, calcium, magnesium,etc.), ammonium or substituted-ammonium cation. Alkyl ethoxylatedsulfates as well as alkyl propoxylated sulfates are contemplated herein.Specific examples of substituted ammonium cations include methyl-,dimethyl-, trimethyl-ammonium cations and quaternary ammonium cationssuch as tetramethyl-ammonium and dimethyl piperdinium cations and thosederived from alkylamines such as ethylamine, diethylamine,triethylamine, mixtures thereof, and the like. A variety of suchsurfactants are also generally disclosed in U.S. Pat. No. 3,929,678,issued Dec. 30, 1975 to Laughlin, et al. at Column 23, line 58 throughColumn 29, line 23 (herein incorporated by reference).

The compositions of the present invention comprise from 0.1% to 30% byweight of the total composition of said anionic surfactant or mixturesthereof, preferably from 0.5% to 15%, most preferably 0.5% to 5%.

The optional co-surfactant

The compositions herein may comprise additional, non anionicsurfactants. Suitable such co-surfactants include nonionic, cationic andamphoteric surfactants.

Cationic detersive surfactants suitable for use in compositions of thepresent invention are those having a long-chain hydrocarbyl group.Examples of such cationic surfactants include the ammonium surfactantssuch as alkyldimethylammonium halogenides, and those surfactants havingthe formula

    [R.sup.2 (OR.sup.3).sub.y ][R.sup.4 (OR.sup.3).sub.y ].sub.2 R.sup.5 N.sup.+ X.sup.31

wherein R² is an alkyl or alkyl benzyl group having from about 8 toabout 18 carbon atoms in the alkyl chain, each R³ is selected from thegroup consisting of --CH₂ CH₂ --, --CH₂ CH(CH₃)--, --CH₂ CH(CH₂ OH)--,--CH₂ CH₂ CH₂ --, and mixtures thereof; each R⁴ is selected from thegroup consisting of C₁ -C₄ alkyl, C₁ -C₄ hydroxyalkyl, benzyl ringstructures formed by joining the two R⁴ groups, --CH₂ CHOH--CHOHCOR⁶CHOHCH₂ OH wherein R⁶ is any hexose or hexose polymer having a molecularweight less than about 1000, and hydrogen when y is not 0; R⁵ is thesame as R⁴ or is an alkyl chain wherein the total number of carbon atomsof R² plus R⁵ is not more than about 18; each y is from 0 to about 10and the sum of the y values is from 0 to about 15; and X is anycompatible anion.

Other cationic surfactants useful herein are also described in U.S. Pat.No. 4,228,044, Cambre, issued Oct. 14, 1980, incorporated herein byreference.

Ampholytic surfactants are also suitable for use in the compositions ofthe present invention. These surfactants can be broadly described asaliphatic derivatives of secondary or tertiary amines, or aliphaticderivatives of heterocyclic secondary and tertiary amines in which thealiphatic radical can be straight- or branched-chain. One of thealiphatic substituents contains at least about 8 carbon atoms, typicallyfrom about 8 to about 18 carbon atoms, and at least one contains ananionic water-solubilizing group, e.g., carboxy, sulfonate, sulfate. SeeU.S. Pat. No. 3,929,678 to Laughlin et al., issued Dec. 30, 1975 atcolumn 19, lines 18-35 (herein incorporated by reference) for examplesof ampholytic surfactants.

Zwitterionic surfactants are also suitable for use in the presentcompositions. These surfactants can be broadly described as derivativesof secondary and tertiary amines, derivatives of heterocyclic secondaryand tertiary amines, or derivatives of quaternary ammonium, quaternaryphosphonium or tertiary sulfonium compounds. See U.S. Pat. No. 3,929,678to Laughlin et al., issued Dec. 30, 1975 at column 19, line 38 throughcolumn 22, line 48 (herein incorporated by reference) for examples ofzwitterionic surfactants.

Semi-polar nonionic surfactants are a special category of nonionicsurfactants which include water-soluble amine oxides containing onealkyl moiety of from about 10 to about 18 carbon atoms and 2 moietiesselected from the group consisting of alkyl groups and hydroxyalkylgroups containing from about 1 to about 3 carbon atoms; water-solublephosphine oxides containing one alkyl moiety of from about 10 to about18 carbon atoms and 2 moieties selected from the group consisting ofalkyl groups and hydroxyalkyl groups containing from about 1 to about 3carbon atoms; and water-soluble sulfoxides containing one alkyl moietyof from about 10 to about 18 carbon atoms and a moiety selected from thegroup consisting of alkyl and hydroxyalkyl moieties of from about 1 toabout 3 carbon atoms.

Semi-polar nonionic detergent surfactants include the amine oxidesurfactants having the formula ##STR1## wherein R³ is an alkyl,hydroxyalkyl, or alkyl phenyl group or mixtures thereof containing fromabout 8 to about 22 carbon atoms; R⁴ is an alkylene or hydroxyalkylenegroup containing from about 2 to about 3 carbon atoms or mixturesthereof; x is from 0 to about 3; and each R⁵ is an alkyl or hydroxyalkylgroup containing from about 1 to about 3 carbon atoms or a polyethyleneoxide group containing from about 1 to about 3 ethylene oxide groups.The R⁵ groups can be attached to each other, e.g., through an oxygen ornitrogen atom, to form a ring structure.

These amine oxide surfactants in particular include C₁₀ -C₁₈ alkyldimethyl amine oxides and C₈ -C₁₂ alkoxy ethyl dihydroxy ethyl amineoxides.

Preferred co-surfactants for use herein are nonionic surfactants.Suitable nonionic surfactants herein comprise polyethylene,polypropylene, and polybutylene oxide condensates of alkyl phenols, withthe polyethylene oxide condensates being preferred. These compoundsinclude the condensation products of alkyl phenols having an alkyl groupcontaining from about 6 to about 14 carbon atoms, preferably from about8 to about 14 carbon atoms, in either a straight-chain or branched-chainconfiguration with the alkylene oxide. In a preferred embodiment, theethylene oxide is present in an amount equal to from about 5 to about 25moles, more preferably from about 3 to about 15 moles, of ethylene oxideper mole of alkyl phenol. Commercially available nonionic surfactants ofthis type include Igepal™ CO-630, marketed by the GAF Corporation; andTriton^(MT) X-45, X-114, X-100 and X-102, all marketed by Rohm & HaasCompany. These surfactants are commonly referred to as alkylphenolalkoxylates (e.g., alkyl phenol ethoxylates).

The condensation products of primary and secondary aliphatic alcoholswith from about 1 to about 25 moles of ethylene oxide are also suitablefor use herein. The alkyl chain of the aliphatic alcohol can either bestraight or branched, primary or secondary, and generally contains fromabout 8 to about 22 carbon atoms. Preferred are the condensationproducts of alcohols having an alkyl group containing from about 8 toabout 20 carbon atoms, more preferably from about 10 to about 18 carbonatoms, with from about 2 to about 10 moles of ethylene oxide per mole ofalcohol. Examples of commercially available nonionic surfactants of thistype include Tergitol™ 15-S-9 (the condensation product of C₁₁ -C₁₅linear alcohol with 9 moles ethylene oxide), Tergitol™ 24-L-6 NMW (thecondensation product of C₁₂ -C₁₄ primary alcohol with 6 moles ethyleneoxide with a narrow molecular weight distribution), both marketed byUnion Carbide Corporation; Neodol™ 45-9 (the condensation product of C₁₄-C₁₅ linear alcohol with 9 moles of ethylene oxide), Neodol™ 23-6.5 (thecondensation product of C₁₂ -C₁₃ linear alcohol with 6.5 moles ofethylene oxide), Neodol™ 45-7 (the condensation product of C₁₄ -C₁₅linear alcohol with 7 moles of ethylene oxide), Neodol™ 45-4 (thecondensation product of C₁₄ -C₁₅ linear alcohol with 4 moles of ethyleneoxide), marketed by Shell Chemical Company, and Kyro™ EOB.

Also useful as an additional nonionic surfactant are thealkylpolysaccharides disclosed in U.S. Pat. No. 4,565,647, Llenado,issued Jan. 21, 1986, having a hydrophobic group containing from about 6to about 30 carbon atoms, preferably from about 10 to about 16 carbonatoms and polysaccharide, e.g., a polyglycoside, hydrophilic groupcontaining from about 1.3 to about 10, preferably from about 1.3 toabout 3, most preferably from about 1.3 to about 2.7 saccharide units.Any reducing saccharide containing 5 or 6 carbon atoms can be used,e.g., glucose, galactose, and galactosyl moieties can be substituted forthe glucosyl moieties. (Optionally the hydrophobic group is attached atthe 2-, 3-, 4-, etc. positions thus giving a glucose or galactose asopposed to a glucoside or galactoside.) The intersaccharide bonds canbe, e.g., between the one position of the additional saccharide unitsand the 2-, 3-, 4-, and/or 6- positions of the preceding saccharideunits.

Optionally, and less desirably, there can be a polyalkkyleneoxide chainjoining the hydrophobic moiety and the polysaccharide moiety. Thepreferred alkyleneoxide is ethylene oxide. Typical hydrophobic groupsinclude alkyl groups, either saturated or unsaturated, branched orunbranched containing from about 8 to about 18, preferably from about 10to about 16, carbon atoms. Preferably, the alkyl group can contain up toabout 3 hydroxy groups and/or the polyalkyleneoxide chain can contain upto about 10, preferably less than 5, alkyleneoxide moieties. Suitablealkyl polysaccharides are octyl, nonyldecyl, undecyldodecyl, tridecyl,tetradecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl, di-, tri-,tetra-, penta-, and hexaglucosides, galactosides, lactosides, glucoses,fructosides, fructoses and/or galactoses. Suitable mixtures includecoconut alkyl, di-, tri-, tetra-, and pentaglucosides and tallow alkyltetra-, penta-, and hexaglucosides.

The preferred alkylpolyglycosides have the formula

    R.sup.2 O(C.sub.n H.sub.2n O).sub.t (glucosyl).sub.x

wherein R² is selected from the group consisting of alkyl, alkylphenyl,hydroxyalkyl, hydroxyalkylphenyl, and mixtures thereof in which thealkyl groups contain from about 10 to about 18, preferably from about 12to about 14, carbon atoms; n is 2 or 3, preferably 2; t is from 0 toabout 10, preferably 0; and x is from about 1.3 to about 10, preferablyfrom about 1.3 to about 3, most preferably from about 1.3 to about 2.7.The glycosyl is preferably derived from glucose. To prepare thesecompounds, the alcohol or alkylpolyethoxy alcohol is formed first andthen reacted with glucose, or a source of glucose, to form the glucoside(attachment at the 1-position). The additional glycosyl units can thenbe attached between their 1-position and the preceding glycosyl units2-, 3-, 4- and/or 6- position, preferably predominantely the 2-position.

Although not preferred, the condensation products of ethylene oxide witha hydrophobic base formed by the condensation of propylene oxide withpropylene glycol are also suitable for use herein. The hydrophobicportion of these compounds will preferably have a molecular weight offrom about 1500 to about 1800 and will exhibit water insolubility. Theaddition of polyoxyethylene moieties to this hydrophobic portion tendsto increase the water solubility of the molecule as a whole, and theliquid character of the product is retained up to the point where thepolyoxyethylene content is about 50% of the total weight of thecondensation product, which corresponds to condensation with up to about40 moles of ethylene oxide. Examples of compounds of this type includecertain of the commercially available Pluronic™ surfactants, marketed byBASF.

Also not preferred, although suitable for use as nonionic surfactantsherein are the condensation products of ethylene oxide with the productresulting from the reaction of propylene oxide and ethylenediamine. Thehydrophobic moiety of these products consists of the reaction product ofethylenediamine and excess propylene oxide, and generally has amolecular weight of from about 2500 to about 3000. This hydrophobicmoiety is condensed with ethylene oxide to the extent that thecondensation product contains from about 40% to about 80% by weight ofpolyoxyethylene and has a molecular weight of from about 5000 to about11000. Examples of this type of nonionic surfactant include certain ofthe commercially available Tetronic™ compounds, marketed by BASF.

Other suitable nonionic surfactants for use hrein include polyhydroxyfatty acid amides of the structural formula: ##STR2## wherein : R¹ is H,C₁ -C₄ hydrocarbyl, 2-hydroxy ethyl, 2-hydroxypropyl, or a mixturethereof, preferably C₁ -C₄ alkyl, more preferably C₁ or C₂ alkyl, mostpreferably C₁ alkyl (i.e., methyl); and R² is a C₅ -C₃₁ hydrocarbyl,preferably straight chain C₇ -C₁₉ alkyl or alkenyl, more preferablystraight chain C₉ -C₁₇ alkyl or alkenyl, most preferably straight chainC₁₁ -C₁₇ alkyl or alkenyl, or mixtures thereof; and Z is apolyhydroxyhydrocarbyl having a linear hydrocarbyl chain with at least 3hydroxyls directly connected to the chain, or an alkoxylated derivative(preferably ethoxylated or propoxylated) thereof. Z preferably will bederived from a reducing sugar in a reductive amination reaction; morepreferably Z is a glycityl. Suitable reducing sugards include glucose,fructose, maltose, lactose, galactose, mannose, and xylose. As rawmaterials, high dextrose corn syrup can be utilized as well as theindividual sugars listed above. These corn syrups may yield a mix ofsugar components for Z. It should be understood that it is by no meansintended to exclude other suitable raw materials. Z preferably will beselected from the group consisting of --CH₂ --(CHOH)_(n) --CH₂ OH,--CH(CH₂ OH)--(CHOH)_(n-1) --CH₂ OH, --CH₂ --(CHOH)₂ (CHOR')(CHOH)--CH₂OH, where n is an integer from 3 to 5, inclusive, and R' is H or acyclic or aliphatic monosaccharide, and alkoxylated derivatives thereof.Most preferred are glycityls wherein n is 4, particularly --CH₂--(CHOH)₄ --CH₂ OH.

In Formula (I), R¹ can be, for example, N-methyl, N-ethyl, N-propyl,N-isopropyl, N-butyl, N-2-hydroxy ethyl, or N-2-hydroxy propyl.

R² --CO--N< can be, for example, cocarnide, stearamide, oleamide,lauramide, myristamide, capricamide, palmitarnide, tallowamide, etc.

Z can be 1-deoxyglucityl, 2-deoxyfructityl, 1-deoxymaltityl,1-deoxylactityl, 1-deoxygalactityl, 1-deoxymannityl,1-deoxymaltotriotityl, etc.

Preferred for use as nonionic surfactants herein are polyethylene oxidecondensates of alkyl phenols, condensation products of primary andsecondary aliphatic alcohols with from about 1 to about 25 moles ofethyelene oxide, alkylpolysaccharides, and mixtures thereof. Mostpreferred are C₈ -C₁₄ alkyl phenol ethoxylates having from 3 to 15ethoxy groups and C₈ -C₁₈ alcohol ethoxylates (preferaby C₁₀ avg.)having from 2 to 10 ethoxy groups, and mixtures thereof. Preferredco-surfactants for use herein are nonionic surfactants for theircleaning action on grease.

The compositions herein may comprise from 0.2% to 90% by weight of thetotal composition of said co-surfactants or mixtures thereof, preferablyfrom 1% to 50%, most preferably from 2% to 20%.

The positive divalent ions

As a second essential ingredient, the compositions herein comprisepositive divalent ions in amounts so as to saturate the anionicsurfactant present in the composition. By "saturate", it is meant hereinthat there should be enough positive divalent ions to bind substantiallyall the anionic surfactant--i.e. the negative charges of the anionicsurfactant--present in the composition, i.e. at least 75% of the anionicsurfactant, preferably at least 80%, most preferably at least 90% or allof anionic surfactant. Different species of anionic surfactants havedifferent number of anions per mole of surfactant. Thus, for a 100%saturation, if X is the number of negative charges per mole of anionicpresent in the composition, the compositions herein will comprisepositive divalent ions in a molar ratio of positive divalent ions toanionic surfactant of at least X:2. And for the purpose of the presentinvention and the amount of positive divalent ions needed therein, theform--protonated or not--in which the anions of the anionic surfactantare present is not critical.

Suitable positive divalent ions for use herein include Mg²⁺, Ba²⁺, Fe²⁺,Ca²⁺, Zn²⁺ and Ni²⁺. Most Preferred are Mg²⁺ and Ca²⁺, or mixturesthereof. The ions can be introduced in the compositions in any form. Asfar as Mg is concerned, MgCl₂ has been found to be commerciallyattractive. However MgSO₄ and MgNO₃ are also suitable source of Mg ionsfor the compositions herein. Without wishing to be bound by theory, wespeculate that the ions herein somehow prevent the builder from bindingwith the calcium in the marble, without preventing the builder fromperforming in the cleaning operation. In another embodiment, salts ofthe anionic surfactants and the divalent positive ions can bepre-formed, before they are introduced in the composition

The pH

As a third essential characteristic, the compositions herein areformulated at a mildly acidic to mildly alkaline pH. Accordingly, thecompositions herein preferably have a pH between 6 and 9, morepreferably between 6.5 and 8, and most preferably between 6.5 and 7.5.At lower pH, the composition would damage marble while, at higher pH, itwould damage lacquers. Interestingly, even in neutral pH in which thecompositions herein can be formulated, damage to marble would beobserved in the abscence of the saturating ions. The pH of thecompositions herein can be adjusted by any of the means well known tothe man skilled in the art, such as addition of NaOH, KOH,MEA,TEA,MDEA,K2CO3,Na₂ CO₃ and the like, or sulphuric acid, nitric acid,hydrochloric acid, acetic acid and the like.

Free of strong builders

It is essential that the compositions herein be free of strong builders.By strong builders, it is meant herein polycarboxylates andpolyphosphates described hereinbelow:

Strong polycarboxylates builders excluded herein are organicpolycarboxylates where the highest LogKa, measured at 25° C./0.1M ionicstrength is between 3 and 8, wherein the sum of the LogKCa+LogKMg,measured at 25° C./0.1M ionic strength is higher than 4, and whereinLogKCa=LogKMg±2 units, measured at 25° C./0.1M ionic strength.

Such polycarboxylates include citrate and complexes of the formula:

    CH(A)(COOX)--CH(COOX)--O--CH(COOX)--CH(COOX)(B)

wherein A is H or OH; B is H or --O--CH(COOX)--CH₂ (COOX); and X is H ora salt-forming cation. For example, if in the above general formula Aand B are both H, then the compound is oxydissuccinic acid and itswater-soluble salts. If A is OH and B is H, then the compound istartrate monosuccinic acid (TMS) and its water-soluble salts. If A is Hand B is --O--CH(COOX)--CH₂ (COOX), then the compound is tartratedisuccinic acid (TDS) and its water-soluble salts. Mixtures of thesebuilders are especially preferred for use herein. Particularly TMS toTDS, these builders are disclosed in U.S. Pat. No. 4,663,071, issued toBush et al., on May 5, 1987.

Still other ether polycarboxylates excluded herein include copolymers ofmaleic anhydride with ethylene or vinyl methyl ether, 1, 3, 5-trihydroxybenzene-2, 4, 6-trisulfonic acid, and carboxymethyloxysuccinic acid.

Other polycarboxylate builders excluded herein are the etherhydroxypolycarboxylates represented by the structure:

    H0--[C(R)(COOM)--C(R)(COOM)--O].sub.n --H

wherein M is hydrogen or a cation wherein the resultant salt iswater-soluble, preferably an alkali metal, ammonium or substitutedammonium cation, n is from about 2 to about 15 (preferably n is fromabout 2 to about 10, more preferably n averages from about 2 to about 4)and each R is the same or different and selected from hydrogen, C₁₋₄alkyl or C₁₋₄ substituted alkyl.

Excluded ether polycarboxylates are also cyclic compounds, particularlyalicyclic compounds, such as those described in U.S. Pat. Nos.3,923,679; 3,835,163; 4,158,635; 4,120,874 and 4,102,903, all of whichare incorporated herein by reference, particularly dipicolinic acid andchelidanic acid.

Also excluded polycarboxylates herein are mellitic acid, succinic acid,polymaleic acid, benzene 1,3,5-tricarboxylic acid, benezenepentacarboxylic acid, and carboxymethyloxysuccinic acid, and solublesalts thereof.

Still excluded carboxylate builders herein are the carboxylatedcarbohydrates disclosed in U.S. Pat. No. 3,723,322, Diehl, issued Mar.28, 1973, incorporated herein by reference.

Other excluded carboxylates herein are alkali metal, ammonium andsubstituted ammonium salts of polyacetic acids. Examples of polyaceticacid builder salts are sodium, potassium, lithium, ammonium andsubstituted ammonium salts of ethylenediamine, tetraacetic acid andnitrilotriacetic acid.

Other excluded polycarboxylates herein are those also known asalkyliminoacetic builders such as methyl imino diacetic acid, alaninediacetic acid, methyl glycine diacetic acid, hydroxy propylene iminodiacetic acid and other alkyl imino acetic acid builders.

Also excluded from the compositions of the present invention are the3,3-dicarboxy-4-oxa-1,6-hexanediotes and the related compounds disclosedin U.S. Pat. No. 4,566,984, Bush, issued Jan. 28, 1986, incorporatedherein by reference. Succinic acid builders include the C5-C20 alkylsuccinic acids and salts thereof, particularly dodecenylsuccinic acid.Alkyl succinic acids excluded herein typically are of the generalformula R--CH(COOH)CH₂ (COOH) i.e., derivatives of succinic acid,wherein R is hydrocarbon, e.g., C₁₀ -C₂₀ alkyl or alkenyl, or wherein Rmay be substituted with hydroxyl, sulfo, sulfoxy or sulfonesubstituents, all as described in the above-mentioned patents.

Specific examples of succinate builders excluded herein arelaurylsuccinate, myristylsuccinate, palmitylsuccinate,2-dodecenylsuccinate, 2-pentadecenylsuccinate, and the like.

Other examples of excluded builders are sodium and potassiumcarboxymethyloxymalonate, carboxymethyloxysuccinate,cis-cyclo-hexanehexacarboxylate, cis-cyclopentane-tetracarboxylate,water-soluble polyacrylates and the copolymers of maleic anhydride withvinyl methyl ether or ethylene.

Other excluded polycarboxylates are the polyacetal carboxylatesdisclosed in U.S. Pat. No. 4,144,226, Crutchfield et al., issued Mar.13, 1979, incorporated herein by reference.

Excluded polycarboxylate builders are also disclosed in U.S. Pat. No.3,308,067, Diehl, issued Mar. 7, 1967, incorporated herein by reference.Such materials are the water-soluble salts of homo- and copolymers ofaliphatic carboxylic acids such as maleic acid, itaconic acid, mesaconicacid, fumaric acid, aconitic acid, citraconic acid and methylenemalonicacid.

Excluded polyphosphonates herein are the alkali metal, ammonium andalkanolammonium salts of polyphosphates (exemplified by thetripolyphosphates, pyrophosphates, and glassy polymericmeta-phosphates), phosphonates.

The compositions herein can further comprise a variety of well knownoptional ingredients, including perfumes, and dyes. However, thecompositions herein are free of builders and they should besubstantially free of solvents which would otherwise damage lacquers.

Particularly preferred compositions herein comprise an effective amountof a carbonate of the formula XHCO₃, where X is an alkali metal,particularly K⁺, Na⁺, or NH₄ ⁺. Indeed, apart from the pH adjustingeffect just described, we have found that the presence of thosecompounds furher improves the safety of the compositions herein todelicate surfaces. Without wishing to be bound by theory, it is believedthat the compounds react with the calcium on the surface of marble, toform an insoluble calcium carbonate salt at the marble/solutioninterface, creating a protective layer. Using these compounds inaddition to the saturation technology described hereinabove provides asynergetic effect on delicate surface safety. The amount of thesecompounds needed in the compositions herein can be determined by trialand error, but appears to lie in the range of from 0.05% to 0.4% byweight of the total composition, preferably from 0.05% to 0.1%. Cautionneeds to be exercised however in that we have observed that too high anamount of XHCO₃ may raise be dertimental to surface safety on lacqueredwood.

The present invention further encompasses a method of cleaning marble orlacquered surfaces. In that method, an effective amount of a compositionas herein before described is applied onto said marble or lacqueredsurface, and said composition is optionally removed.

Depending on the surface which is being cleaned, the compositions hereincan be used undiluted, i.e. neat, or diluted. Typically, when used onlarge surfaces, such as floors, the compositions herein are used indiluted form, i.e. at dilution levels of from about 0.5% to 1.5%,depending on how concentrated the product is. In such dilutedconditions, the compositions herein are applied to said surface, andleft to dry, i.e. no rinsing is required. In order to remove toughstains on these surfaces the product can also be applied neat on thesurface to remove the encrustated dirt much more easily. When used onsmaller surfaces, e.g. bathroom walls which can be made out of marble,neat usage of the composition will be preferred. In neat usage, it ispreferable that the composition should be removed, i.e. rinsed off afterit has been applied to clean.

The present invention will be further illustrated by the followingexamples.

EXAMPLES

The following compositions were made by mixing the listed ingredients inthe listed proportions. These compositions were used neat to cleanmarble and dilute to clean lacquered wooden floors. Excellent cleaningand surface safety performance was observed.

    ______________________________________                                                  Compositions                                                        Ingredients                                                                             (weight %)                                                          Example N 1       2       3     4     5     6                                 ______________________________________                                        NaPS      1.0     3.0     --    --    4.0   3.0                               NaLAS     --      --      2.0   --    --    --                                NaAE.sub.2 S                                                                            --      --      --    2.0   --    --                                R-AE.sub.x                                                                              6.0     4.0     5.0   6.0   4.0   4.0                               Mg         0.08    0.20    0.13  0.12 --    --                                NaHCO.sub.3                                                                             --       0.10    0.11  0.10 --    --                                Na2HPO4   --      --      --    --    0.2   --                                Na2H3P3O10                                                                              --      --      --    --    --     0.15                             pH        7.1     7.5     7     7.3   7.4   7.5                               water and minors                                                                        up to 100%                                                          ______________________________________                                    

What is claimed is:
 1. A method of cleaning marble or lacquered surfaceswith an aqueous composition having a pH of 6 to 9, said compositioncomprising:(a) 0.1% to 30% of anionic surfactant, and (b) positivedivalent ions selected from the group consisting of Mg₂ ⁺, Ca₂ ³⁰ andmixtures thereof in an amount 0.05% to 4% by weight whereby the molarratio of said ions to negative charges per mole of anionic surfactant isat least 2; (c) from about 0.05% to about 0.4% by weight of a carbonateof the formula XHCO₃ where X is an alkali metal or ammonium ion;whereinsaid composition is free of polyphosphate builders and strong organicpolycarboxylate builders, said strong polycarboxylate builders beingthose wherein the highest LogKa, measured at 25° C./0.1M ionic strengthis between 3 and 8, wherein the sum of LogKCa+LogKMg measured at 25°C./0.1M ionic strength is greater than 4 and wherein LogCa equalsLogMg±2 units, measured at 25° C./0.1M ionic strength, said methodcomprising the step of applying the said composition to said marble orlacquered surface and thereafter optionally removing said compositionfrom said surface.
 2. A method according to claim 1 wherein saidcomposition is formulated in a pH range of from about 6.5 to about
 8. 3.A method according to claim 2 wherein said composition is formulated ina pH range of from about 6.5 to about 7.5.
 4. A method according toclaim 1 wherein said composition comprises from about 0.1% to about 20%by weight of the total composition of said anionic surfactant.
 5. Amethod according to claim 4 wherein said composition comprises fromabout 0.1% to about 10% by weight of the total composition of saidanionic surfactant.
 6. A method according to claim 1 wherein saidcomposition further includes a nonionic co-surfactant.
 7. A methodaccording to any of claims 6 or 1 wherein said composition is applied indiluted form at a concentration of 0.5 to 1.5%.